Variable speed surfacing machine



June 21, 1932. M, W WILSON 1,864,226

VARIABLE SPEED sunmclne MACHINE Filed April 8, 1,929 2 Sheets-Sheet 1 W I I 75655. JZaaee Wfi lkowz June 21, 1932. M.- w. H. WILSON VARIABLE SPEED SURFACING MACHINE Filed April 8, 1929 2 Sheets-Sheet 2 Patented June 21, 1932 MOSES WrI-I. 'W'ILSONQOF EAST LANSING, MICHIGAN, ASSIGNOR T MOTOR WHEEL GOR- PORATION, OF LANSING,- MICHIGAN, A CORPORATION OF MICHIGAN VARIABLE SPEED SUB-FACING MACHINE Application filed April 8, 1929. Serial No. 353,295.

. fMy invention has to do particularly with an improvement in machines for surfacetreating, asby sanding or filling, objects having other than acylindrical contour. It is old to surface treat wood wheel spokes or.

similar obj ectsby rotating the spoke with its barrel portion in contact with an abradlng or cutting surface.

A traveling belt having an abrasive face filler and a second belt for'r'ubbing it into the poresand wiping off the surplus, the spoke being in the meantime progressively advanced and rotated. V Such machines and practices have been work pieces are truly cylindrical, the progressive movement of the belts and workas also the rotation of thelatter beingconstant, under which conditions uniformity of result would follow.

However, non-uniform results follow where, as in the case of many spoke designs, the body treated is of non-cylindrical shape,

elliptical, oval, squared, or otherwise. In

such circumstances, a constant speed of rotation will result in those portions havmga larger radlus being acted upon to a greater degree than the smaller radius,the surface area corresponding to the major axisas compared with the surface area corresponding to the minor axis. For instance, the abrasive effect will be greater on the corners than on the flat face of a squared spoke, and on the sharper curvature than that of flatter area in the case of an elliptical spoke.

To compensate-for such conditions, it is proposed, according tomy invention,to var the speed of rotation of the spoke-through recurring cycles of acceleration and deceleration corresponding to the periods when .the

portions of different contour are in contact -w1th' the surfacing belt or other medium,ac-

celerated when the more sharply curved area is in contact and decelerated when the flatter area is being acted upon.

To this end I preferably, though not necessarily, maintain a constantforward travel of the surfacing medium, but provide by means of lrregular gearlng, eccentric or elliptical,

for advancing and rotating the spokes at varying speeds at predetermined positions.

In order that the invention may be read-' ily understood and readily practiced, a preferred embodiment of the same is set forth, for illustrative and not restrictive purposes, in the accompanying drawings, wherein Fig. 1 is a side elevation of those. portions of a machine necessary. to anundersta-nding of the invention; predicated upon the assumption that the V No. 1,660,535, issued February 28, 1928 upon.

the application of A. S. Van Halteren, a machine there set forth as applied to the filling of spokes preliminary to painting and a machine equally well adapted to surfacing by sanding. Various details of assembly incident to machines of that type are not deemed necessary to be completely illustrated herein, being well understood in the art.

Having reference to the drawings, a belt 11, suitably driven, passes over pulleys 12 and 13, while a second beltl, suitably driven, I

traverses pulleys 15and 16. Belt 11 may advantageously be faced with an abrading material such as sand of coarse texture, while belt 14; may be faced with a finishing abrasive material of finer texture; or belt 11 may be coated with a filler paste for application to the objects being treated, while the belt 14 may serve as a wiping belt for rubbing the material into the pores of the wood and wiping off the surplus. The belts will be hereafter referred to, without restrictive intent, as abradinggbelts and the machine'as a sanding machine, itbeing understood that without substantial modification the machinemay besemployedfor variously surfacing objects. "Upon -the shaft 17, driven by suitable means, is mounted a cage-like frame or reel comprising spaced frame members 18, 19,20 and 21, the member 19 provided with centering head chucks 22 and the 1nember 20 with centering tail spindles 23 spring-pressed at "24 for ease of inserting and removing'from the machmelthespokes orother workpieces illustrated as having their 'head portions 2-5 seated in the head chucks 22and theirba-rrel portions 26'centeredbythe spindles '23. "In "Fig.2, aspoke is shown as missing, this "for the purpose-ofillustrating the-retraction of thespindle'against its spring Qiprior to inserting a spoke. "Upon the axle 27 of each of the head chucks ismounted a pinion '28. The head chucks and tail spindles are mounted in opposed 'coaxialrelation to eachotherand inan annular seriesabout the shaft 17.

A'stationaryrear gear 29 'is'fixe'd upon the machine frame and serves as a toothed rack with which-each of the unions-'28 mesh and-by which they are rotated upon-theirrespective *axesas they revolve in'an orbit about'the shaft '17.

'The objects to'be-treated, spokes fol-ex- -ample,'havin-g one end seated in the head chucks 22 and the otherendreleasablyheld by the springrpressed tail spindles 23, voccupy a position transverse to-their path of revolutionabout thereel axis andalso transverse to the path of the abrading belts 11 and '14. the planes of revolution including barrels of the spokes'being parallel to and included within planes of travel. ofthe belts.

The barrels 26 of the spokesare successively .brought'into andmaintained in continuoussubstantially constant pressure contact with the "belt llby' the rotation of the reel and the 1 belt tension and, as they are atthe same time being rotated by'the piniousQS, the-barrel surface is subjectedto an abrasive actionby the belt. As the spokes: progress, after leaving contact with theabrading belt 11, they come into contact withthe second belt 14,-.whe-reby the surface isfu-rther treated.

The spokes are-thenreleased-from the chucks and-replaced-by others before the chucks next reach the abradingfbelts.

The mechanism thus far described and operating in the manner set forth would serve to surface the spoke barrels uniformly, provided the barrels were of cylindrical contour or circular cross section. The modern wheel spoke is, however, not usually circular in cross section or of cylindrical surface contour but departs from regularity of curvature, tending towards an elliptical section, as shown in Fig. 3, or a squared section, as shown 3 in Fig. 4. Withrthamachinepas thus f-ar described employedfor sanding, the area corresponding to the major axis of the elliptical spoke and corresponding to the corners of the squared spoke wouldibe subjected to a greater abra'ding actionthan the area correspondingtotheminor axis, the result being a tendency towards cutting the spoke down to a circular section.

In order to compensate for this difference in contour, the train-of gearing connecting the drive pulley with'theaxle 177'. Off the reel! com- *prisessgea-r members of non-circular, eccentric or elliptical -shape instead ref-circular gears. Eccentric gear elements .-.are iillus 'trated, although it is to be iunderstood *1 that elliptical gears or other equivalent 2 elements may be substituted withoutsdeparture"from the invention. f

To illustrate, the drive pulley :30 transmits power :to the drive shaft 31: journaled. in: the "yoke Ell and carrying a :-pi-nion 1-32 in mesh avith api-nion 33. :U-pon the shaft-3'3 of pinion 33 is secured an eccentric gear 34 whichi i-s in mesh-with another eccentric geare'35 mounted on another shaft 35 carrying. a:.-pinion 36, which latter pinion'is in mesh withail-arge pinion'i 'ihaving fixed :upon its shaft-a= smaller pinion "'38 which in turn-smesheszwithsand :serves to drive the large gear-=39 fixed upon -the shaft' lf'ofthereel.

Obviously other combinations of I gearszi'n train-may be-e-mployeliha-whereby the constant speed of thezpower -shaft 31 isitransmitted to --the ringgearQQ-as a varying speed dueto the incorporation in the train: of. onerorxmore eccentric-or; ellipticalrgears.

" The gear-ratio is such that there are-two accelerations and alternate retardations of the head chucks during -each:rota-t-ion -of*the chuck and spoke 'heldthereby.

Thetwo cycles ofaccelcrati-on and retarda- +ti on during one revolution of the: spoke would applv' where :an elliptical-spoke is beingrsu-r- =-faced. such as that illustrated in- Fig.t'3 'Of the drawing. If, however. a spoke of'rthe cross section as shown in Fig. A were ibeing--sur faced,ithere would be, duringeach:rotationmf the spoke, -acycle comprising fou-ra accelerations and four decelerations or *retardations, the accelerations icorresponding Eto a-thectgime when the corners --we-re ingcontact with "the -sanding lt: and the four retandationsecorrespending to hetime "when thervflatssurtaces ofthe-spoke were-being sanded.

In many cases but one surfacing belt would be employed and the spoke could be given either one or more complete rotations while in contact with the belt. In other cases a second belt would advantageously be employed to give a finer finish to the article; all to accord with the particular kind of work being done and the nature of the surface treatment.

It will thus be observed that according to.

my invention a surfacing machine is provided which by a suitable change of gearing, within the skill of any mechanic, will uniformly operate upon the surface of work pieces having other than a cylindrical contour as distinguished from prior machines of this general type wherein non-uniform results follow a uniform rotation of the work while being treated; that the invention as set out is adapted for embodiment in machines of this type when employed for surfacing in many ways other than that of sanding.

I claim:

1. In a machine for surface treating articles of non-cylindrical contour, the combination with a uniformly traveling treating surface, means for moving the article bodily and means for rotating the article in rubbing contact with said surface, of means for varying the axial speed of rotation through a cycle during the period of such contact.

2. In a machine for surface treating articles of non-cylindrical contour, the combination with a treating surface, and means for bodily moving and rotating the article in rubbing contact with said surface, of means for increasing the speed of bodily movement and speed of rotation of the article when the area in contact corresponds to a greater radius and decreasing the speed when the contact area corresponds to a smaller radius.

3. In a machine for surface treating articles of a non-cylindrical contour, the combination with a treating surface, a reel revolving peripherally adjacent said surface, an annular toothed rack disposed adjacent the reel periphery, a plurality of article-holding chucks rotatably mounted on the reel periphery in geared relation to the annular rack, and means for revolving the reel at variable sreeds with the surfaces of the articles carried in the chucks in rubbing contact with. the treating surface.

4. In a machine for surface treating articles of a non-cylindrical contour, the combination with a treating surface, a reel revolving peripherally adjacent said surface. an annular toothed rack disposed adjacent the reel periphery, a plurality of article-holding chucks rotatably mounted on the reel periphery in geared relation to the annular rack, and means for revolving the reel at variable speeds with the surfaces of the articles carried in the chucks in rubbing contact with the treating surface, the speed of revolution of the reel and consequent forward travel and rubbing contact periodically.

rotation of the chucks beingincreased when areas of the articles corresponding to a-great-' bination .of a moving surfacing belt, a reel revolving peripherally adj acent the belt, an annular toothed rack disposed adjacent-the reel periphery, a plu'rality of article-holding. chucks rotatably mounted on the reel periphery in geared'relation to the annular-rack, and means for revolving the reel' at'varia'ble speeds with the surfaces of the articles carrieid in the chucks in rubbing contact with the betfl 6. Ina machine for surface treating articles of a non-cylindrical contour, the combination of a moving surfacing belt, a reel revolving peripherally adjacent the belt, an annular toothed rack disposed adjacent the reel periphery, a plurality of article-holding chucks rotatably mounted on the reel periphery in geared relation to the annular rack, and means for revolving the reel at variable speeds with the surfaces of the articles carried in the chucks in rubbing contact with the belt,

the speed of revolution of the reel and consequent forward movement and rotation of the chucks being increased when areas of the articles corresponding to a greater radius are in contact with the belt and decreased when areas are in contact corresponding to a smaller radius.

7. In a machine for surface treating articles of a non-cylindrical contour, the combination of a moving surfacing belt, a reel revolving peripherally adjacent the belt, an annular toothed rack disposed adjacent the reel periphery, a plurality of article-holding chucks rotatably mounted on the reel periphery in geared relation to the annular rack, and means comprising a gear train including eccentric ears for revolving the reel at variable spee s with the surfaces of the articles carried in the chucks in rubbing contact with the belt, the speed of revolution of the reel and consequent forward movement and rotation of the chucks being increased when cal ticles, a treating belt, means for imparting to the belt a progressive traveling movement in an arcuate path, holders for the articles to be treated, means for moving said holders in an orbit tangential to the arc of the belt travel and in rubbing contact therewith,

means for axially rotating said holders and articles, and means for varying the axial speed of rotation and the surface speed of i9; In '.a:maohine; forr-smriiaceitreatingzartizcles 10f :n-ongcylindrioal 1' surface rcontour ne treatingbeltgmeans'for imparting to the'belt :zaaprogressive gtravelingimovement in an arouate pathgholders forflthe articlesto be treated,

means for moving said "holders in an orbit tan ential'toithe arc of the belt travel and in J rub ing c0ntact;therewith,. meansfor" axially v "rotating sai1d1holders and articles, and means for varying thezaxial ;speed of rotation "and the surfacespeed of rubbing contact :periodisally proportionately to the increase and deycrease inradial dimensions of those portions of the-article being treated.

.'In testimony whereof-Irhave hereunto subascribed myrnzune.

MOSES W. H. WILSON 

